Asset Accumulation and Short Term Employment

This paper investigates the search and consumption behavior of workers as they move between readily available low wage employment and uncertain search for a high wage job. Analytic results derived from our model include: (1) voluntary planned quits occur in a cyclical pattern, (2) consumption while searching falls over time until either a good job is found or assets run out and the worker accepts a low wage job, (3) consumption during low wage employment is less than earnings, and (4) the durations of job search and employment as well as the pattern of consumption are related to turnover costs and wages. Empirical evidence from the 1995 Canadian out of Employment Panel (COEP) broadly supports these relationships. In these data, there exists a high incidence of displaced workers taking temporary low wage jobs. Examining the income, consumption and savings patterns of workers in different regimes, we fiind that these accord with the theoretical predictions.unemployment; search; consumption; assets

A model of large-scale proteome evolution

The next step in the understanding of the genome organization, after the determination of complete sequences, involves proteomics. The proteome includes the whole set of protein-protein interactions, and two recent independent studies have shown that its topology displays a number of surprising features shared by other complex networks, both natural and artificial. In order to understand the origins of this topology and its evolutionary implications, we present a simple model of proteome evolution that is able to reproduce many of the observed statistical regularities reported from the analysis of the yeast proteome. Our results suggest that the observed patterns can be explained by a process of gene duplication and diversification that would evolve proteome networks under a selection pressure, favoring robustness against failure of its individual components

Applying Downscaled Global Climate Model Data to a Hydrodynamic Surface-Water and Groundwater Model

Precipitation data from Global Climate Models have been downscaled to smaller regions. Adapting this downscaled precipitation data to a coupled hydrodynamic surface-water/groundwater model of southern Florida allows an examination of future conditions and their effect on groundwater levels, inundation patterns, surface-water stage and flows, and salinity. The downscaled rainfall data include the 1996-2001 time series from the European Center for MediumRange Weather Forecasting ERA-40 simulation and both the 1996-1999 and 2038-2057 time series from two global climate models: the Community Climate System Model (CCSM) and the Geophysical Fluid Dynamic Laboratory (GFDL). Synthesized surface-water inflow datasets were developed for the 2038-2057 simulations. The resulting hydrologic simulations, with and without a 30-cm sea-level rise, were compared with each other and field data to analyze a range of projected conditions. Simulations predicted generally higher future stage and groundwater levels and surface-water flows, with sea-level rise inducing higher coastal salinities. A coincident rise in sea level, precipitation and surface-water flows resulted in a narrower inland saline/fresh transition zone. The inland areas were affected more by the rainfall difference than the sea-level rise, and the rainfall differences make little difference in coastal inundation, but a larger difference in coastal salinities

Cosmogenic-neutron activation of TeO2 and implications for neutrinoless double-beta decay experiments

Flux-averaged cross sections for cosmogenic-neutron activation of natural tellurium were measured using a neutron beam containing neutrons of kinetic energies up to $\sim$800 MeV, and having an energy spectrum similar to that of cosmic-ray neutrons at sea-level. Analysis of the radioisotopes produced reveals that 110mAg will be a dominant contributor to the cosmogenic-activation background in experiments searching for neutrinoless double-beta decay of 130Te, such as CUORE and SNO+. An estimate of the cosmogenic-activation background in the CUORE experiment has been obtained using the results of this measurement and cross-section measurements of proton activation of tellurium. Additionally, the measured cross sections in this work are also compared with results from semi-empirical cross-section calculations.Comment: 11 pages, 5 figure

Temporal and Spatial Changes in the Pattern of Iba1 and CD68 Staining in the Rat Brain Following Severe Traumatic Brain Injury

We have previously demonstrated that acute treatment with low dose methamphetamine is neuroprotectivein a rat model of severe traumatic brain injury (TBI). Using gene expression analysis, we further showed that methamphetamine treatment significantly reduced the expression of proinflammatory genes after severe TBI. Therefore, to further investigate the potential effects of methamphetamine treatment on the neuroinflammatory response, we examined immunofluorescent staining of Iba1 and CD68, two marker of neuroinflammation, in the rat lateral fluid percussion injury model of severe TBI. In this study, we observed temporal and spatial alterations in the pattern of Iba1 and CD68 labeling within two weeks after severe TBI. In general, methamphetamine treatment did not dramatically alter the pattern of Iba1 and CD68 staining. However, we did observe a unique and significant drug-induced increase of Iba1 labeling within the granule cell layer of the dentate gyrusat 48 hours post injury. We also observed rod-shaped Iba1+ cells within the core lesion in the cortex. These cells showed variable staining with CD68 and aligned most closely with MAP2+ neuronal processes. Thus, acute treatment with low-dose methamphetamine after severe TBI caused a transient bilateral increase of Iba1+ cells within the granule layer of the dentate gyrus but did not alter the overall temporal and regional pattern of Iba1 and CD68 staining within the cortex, periventricular white matter, fimbria, or thalamus

“Off the beaten map”: Navigating with digital maps on moorland

Resources made available through the digital map app change, but do not replace, the skills of “ordinary wayfinding.” Looking at the challenges of wayfinding with new mobile devices helps inform the development of digital mapping tools for navigating through difficult terrain. With this background in mind, in this paper we consider how the contemporary navigational resources of mobile devices with GPS, and the resources of countryside landscape features, are brought together in visiting a tourist site. We analyse video data from groups walking across unfamiliar moorland terrain, following a guide and map app which takes them on a tour of a remote Roman marching camp in the Brecon Beacons National Park, Wales. Following an ethnomethodological and conversation analytic approach, we examine three instances of navigational work for paired walkers as they traverse the moorland. The three fragments are of: an orientational struggle to establish where to go next; a routine check to select a path; and the discovery of a feature mentioned in the guide. Across the three episodes we explicate how our walkers make sense of the guide and map in relation to investigating the moorland surface. We examine how their ambulatory and undulatory practices on the moorland are tied to their wayfinding practices. While we analyse wayfinding talk, we also attend to the mobile practices of stopping and pausing as part of practical navigational reasoning

Workplace secondhand smoke exposure in the U.S. trucking industry.

BackgroundAlthough the smoking rate in the United States is declining because of an increase of smoke-free laws, among blue-collar workers it remains higher than that among many other occupational groups.ObjectivesWe evaluated the factors influencing workplace secondhand smoke (SHS) exposures in the U.S. unionized trucking industry.MethodsFrom 2003 through 2005, we measured workplace SHS exposure among 203 nonsmoking and 61 smoking workers in 25 trucking terminals. Workers in several job groups wore personal vapor-phase nicotine samplers on their lapels for two consecutive work shifts and completed a workplace SHS exposure questionnaire at the end of the personal sampling.ResultsMedian nicotine level was 0.87 microg/m3 for nonsmokers and 5.96 microg/m3 for smokers. As expected, smokers experienced higher SHS exposure duration and intensity than did nonsmokers. For nonsmokers, multiple regression analyses indicated that self-reported exposure duration combined with intensity, lack of a smoking policy as reported by workers, having a nondriver job, and lower educational level were independently associated with elevated personal nicotine levels (model R2 = 0.52). Nondriver job and amount of active smoking were associated with elevated personal nicotine level in smokers, but self-reported exposure, lack of a smoking policy, and lower educational level were not.ConclusionsDespite movements toward smoke-free laws, this population of blue-collar workers was still exposed to workplace SHS as recently as 2005. The perceived (reported by the workers), rather than the official (reported by the terminal managers), smoking policy was associated with measured SHS exposure levels among the nonsmokers. Job duties and educational level might also be important predictors of workplace SHS exposure

Secondhand smoke exposure and inflammatory markers in nonsmokers in the trucking industry.

BackgroundFew studies have directly assessed the association of secondhand smoke (SHS) with cardiovascular disease-related inflammatory markers, and the findings are inconsistent.ObjectivesWe assessed the association between SHS exposure and the inflammatory markers high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1 (sICAM-1) in 199 nonsmoking U.S. trucking industry workers.MethodsParticipants provided blood samples either by mail (blood drawn at local health care provider near home) or at the work site (blood drawn by research staff on-site) and completed a health and work history questionnaire at the time of blood draw. Exposure to SHS was measured by plasma cotinine concentrations. We used multivariate regression analyses to assess the associations between levels of cotinine and inflammatory markers.ResultsThe median cotinine level was 0.10 ng/mL (interquartile range, 0.04-0.23 ng/mL). The odds ratios of elevated hs-CRP (above highest CRP tertile, 1.5 mg/L) were 2.85 [95% confidence interval (CI), 1.03-7.89] for the high-cotinine group (> 0.215 ng/mL) and 2.80 (95% CI, 1.11-7.10) for the moderate-cotinine group (0.05-0.215 ng/mL), compared with the low-cotinine group (< 0.05 ng/mL), adjusting for age, sex, race, educational level, obesity, previous smoking history, job title, and medical history. Plasma cotinine levels were not associated with IL-6 or sICAM-1.ConclusionsSHS exposure, as assessed by plasma cotinine, was positively associated with hs-CRP in this group of blue-collar workers. The strength of the association with hs-CRP depended on the cut points selected for analysis